Quite often I've flagged answers as NAA and my flag has been marked as helpful but the answer has remained days later. Most of the time it's because the answer has been edited, and I can see some logic in that, but at other times I've been at a loss for an explanation because the post doesn't seem to be even a partial answer where a moderator might dismiss as helpful but not delete.

But several times now I've noticed it's because the OP simply deletes and then undeletes the answer. I've noticed this most on Stack Overflow but here's an example from Electrical Engineering where I checked into it further because I have 10k rep there:

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So I'd like to suggest that a delete / undelete by the OP shouldn't dismiss a post from the low-quality review queue. I feel an edit should be the only thing that invokes that behavior and / or perhaps when something is dismissed allow the original flagger to re-raise a flag. That post was only deleted shortly after I used a custom moderator flag which seems a waste of their time.